Do you, or one of your athletes, have chronic heel pain? Plantar fasciitis that never completely goes away? Heel spurs, even though you are not a cowboy?
If your answer is yes to any of the above questions, you may be interested in a relatively new treatment modality called extracorporeal shock wave therapy (ESWT), a non-invasive procedure in which strong sound waves are directed at the area of pain. The device used for extracorporeal shock wave therapy is very similar to the one currently used in non-surgical treatment of kidney and gall-bladder stones. It's called a lithotriptor device, and it generates strong shock waves at the treatment site. In theory, these shock waves achieve therapeutic results by causing bone-marrow haemorrhages and minor fractures. That sounds rather ghastly, but the controlled trauma is then thought to instigate a healing response in which new bone formation occurs. This potentially eases inflammation in the heel and relieves chronic pain. The ESWT treatment takes about 30 minutes and is performed under local anaesthesia and/or 'twilight' anaesthesia. ESWT is an out-patient procedure and does not require an overnight stay in the hospital.
The effectiveness of extracorporeal shock wave therapy was recently described in a paper presented at the Annual Meeting of the American College of Foot and Ankle Surgeons in New Orleans on February 8, 2001 (http://www.acfas.org/prshckwavthera. html). Shock-wave researcher Kimberly Eickmeier reported the results of a clinical study of 16 patients with chronic plantar fasciitis, each of whom received a minimum of 2,000 low-intensity shocks to the affected heel. Moderately and severely overweight subjects were given two or three treatments totalling 4,000 to 6,000 shocks, respectively.
Amazingly, normal-weight and moderately obese patients reported that their chronic-plantar-fasciitis pain had dropped to zero the day after shock wave therapy (pain was rated on a scale from zero to five, with five representing the most intense-possible discomfort), and even severely obese individuals detected a drop-off in pain. After both six and 12 months of follow-up, pain levels remained low for normal and moderately obese individuals, and there were no reported side effects.
'Achievement of long-term pain relief with shock wave therapy correlated strongly to body mass index, as the normal and moderately obese groups had 80% improvement while the severely obese group improved by just 21%,' said Eickmeier. 'Shock-wave therapy is what we've been waiting for to bring lasting relief for those with chronic, unresponsive heel pain,' continued Eickmeier, who is a podiatric foot and ankle surgeon. 'It's virtually painless, and patients resume normal activity wearing regular shoes the day after the procedure.'
Other research tends to support the idea that extracorporeal shock wave therapy can be an effective treatment for non-responsive plantar fasciitis and heel pain, especially in certain situations. In an investigation carried out recently at Ludwig-Maximilians University in Munich, Germany, 43 patients and 48 heels with chronic cases of plantar fasciitis (five patients had pain in both feet) were clinically examined before and after repetitive low-energy extracorporeal shock wave therapy ('Extracorporeal Shock Wave Application for Chronic Plantar Fasciitis Associated with Heel Spurs: Prediction of Outcome by Magnetic Resonance Imaging,' Journal of Rheumatology, vol. 27(10), pp. 2455-2462, 2000). Standard radiographs of the affected heels were obtained before extracorporeal shock wave therapy to document the existence of calcaneal heel spurs, and magnetic resonance imaging (MRI) was performed before extracorporeal shock wave therapy to evaluate abnormalities of the plantar fascia, the surrounding soft tissue structures, and to check for bone marrow oedema of the heel bone (calcaneus).
The average follow-up period was 19 months, and clinical evaluation of the 48 heels revealed a statistically significant decrease in inflammation. Using the Roles and Maudsley score, an established scoring system for categorising results of treatment following extracorporeal shock wave therapy for patients with plantar fasciitis, 36 patients had satisfactory clinical outcomes, while 12 individuals did not. Interestingly enough, the presence of a calcaneal bone-marrow oedema (revealed by MRI) was the best predictor of a good clinical outcome; if bone marrow-oedema was present before extracorporeal shock wave therapy, it was highly likely that the extracorporeal shock wave therapy would be effective at reducing symptoms.
It also works for tennis elbow
Not surprisingly, extracorporeal shock wave therapy has also been used to treat tennis players suffering from tennis elbow, a condition in which the elbow of the arm holding the racquet becomes inflamed, painful, and stiff. In research carried out at the Orthopaedic University Hospital in Homburg/Saar, Germany, 19 athletes with tennis elbow and 44 individuals with painful heels in which conservative treatment had failed underwent extracorporeal shock wave therapy ('Shock Wave Therapy for Tennis Elbow and Plantar Fasciitis,' Arch Orthop Trauma Surg, vol. 120(5-6), pp. 304-307). Both groups received 3000 shock waves of 0.12 mJ/mm2 three times at weekly intervals. After five and six months of follow-up, pain was significantly reduced in both groups; about 63% of the tennis elbows and 70% of the painful heels achieved either excellent or good results, and the German researchers concluded that extracorporeal shock wave therapy was a useful, conservative treatment for both conditions.
An even longer-term study was also positive for extracorporeal shock wave therapy. In work carried out at the Stadtische Orthopaedic Clinic in Dortmund, Germany, 54 patients received extracorporeal shock wave therapy, 20 of them with extracorporeal shock wave therapy plus ultrasound and 34 with extracorporeal shock wave therapy and X-ray focusing ('5-Years Lithotripsy of Plantar Heel Spur: Experiences and Results - A Follow-Up Study after 36.9 Months,' Z Orthop Ihre Grenzgeb, vol. 136(5), pp. 402-406, 1998). After six weeks, 70 to 79% of the treated individuals were free of pain, and after three years 40 to 68% of them were still discomfort-free. No serious side effects were reported.
Finally, in a well-controlled study carried out in the Department of Orthopaedics at University Hospital in Mainz, Germany, 30 patients who suffered from persistent symptoms for more than 12 months were assigned at random to two groups, real or simulated extracorporeal shock wave therapy. Before beginning the treatment, all other therapies were stopped for a period of six weeks. A fluoroscopy unit was utilised to provide exact localisation of the shock waves, and patients were treated a total of three times at weekly intervals. Each time 1000 impulses of 0.06 mJ/mm2 were given around the heel spur, and follow-ups were done after three, six, 12 and 24 weeks.
An interesting twist to this study was that patients in the placebo group who did not improve after six weeks of follow-up were then offered extracorporeal shock wave therapy therapy and were subsequently checked over an additional 24-week period. The results indicated that extracorporeal shock wave therapy significantly alleviated pain and improved function for all follow-up times, compared to the sham treatment ('Low-Energy Extracorporeal Shock Wave Therapy for Painful Heel: A Prospective Controlled Single-Blind Study,' Arch Orthop Trauma Surg, vol. 115(2), pp. 75-79, 1996).
Of course, the best, most fundamentally sound way to deal with plantar fasciitis and heel pain is to systematically build up the sport-specific strength of the feet and ankles (see SIB, issue 3, page 1). When such strengthening doesn't completely get the job done, however, extracorporeal shock wave therapy appears to be an effective treatment for chronic and difficult-to-treat heel pain and plantar fasciitis. Note, though, that not everyone can receive the therapy; in fact, extracorporeal shock wave therapy is not appropriate for individuals who have a bleeding disorder or who are taking medications that may prolong bleeding or interfere with blood clotting (remember that the shock waves themselves induce some bleeding in bony tissue). ESWT should not be used by children or during pregnancy. In addition, its safety and effectiveness have not been established for those with nerve damage, osteoporosis, rheumatoid arthritis, tarsal tunnel syndrome, diabetic neuropathy, severe peripheral vascular disease, metabolic disorders, and infections. As with any surgical procedure, complications may arise. There have been reports of bruising of the skin, swelling, pain, numbness, tingling, and rupture of the plantar fascia. Misdirected treatment may also result in blood vessel, nerve, or bone damage.